The pathways that lead to the development of tissue-resident lymphocytes, including liver type 1 innate lymphoid cells (ILC1s), remain unclear. We show here that the adult mouse liver contains Lin⁻Sca-1⁺Mac-1⁺ hematopoietic stem cells derived from the fetal liver. This population includes Lin⁻CD122⁺CD49a⁺ progenitors that can generate liver ILC1s but not conventional natural killer cells. Interferon-γ (IFN-γ) production by the liver ILC1s themselves promotes the development of these cells in situ, through effects on their IFN-γR⁺ liver progenitors. Thus, an IFN-γ–dependent loop drives liver ILC1 development in situ, highlighting the contribution of extramedullary hematopoiesis to regional immune composition within the liver.

导致组织驻留淋巴细胞（包括肝脏 1 型先天淋巴细胞 (ILC1)）发育的途径仍不清楚。我们在此表明​​，成年小鼠肝脏含有 Lin ⁻ Sca-1 ⁺ Mac-1 ⁺来自胎儿肝脏的造血干细胞。该群体包括 Lin ⁻ CD122 ⁺ CD49a ⁺祖细胞，可以产生肝脏 ILC1，但不能产生传统的自然杀伤细胞。肝脏 ILC1 本身产生的干扰素-γ (IFN-γ) 通过影响 IFN-γR ⁺肝脏祖细胞，促进这些细胞原位发育。因此，IFN-γ依赖性环路驱动肝脏ILC1原位发育，突出了髓外造血对肝脏内区域免疫组成的贡献。